APP and Alzheimer disease: The triple-transgenic mouse model (which carries three human variants associated with AD: the APP Swedish variant, KM670/671NL, the PSEN1 variant, M146V, and the MAPT variant, P301L) exhibit decreased nocturnal activity (the equivalent of daytime napping in a nocturnal species), increased daytime activity (Sterniczuk et al., 2010) and age-related changes in body temperature rhythms (Knight et al., 2013).